Machine for the continuous casting of molten materials in iron molds or chills

ABSTRACT

A MACHINE FOR THE CONTINUOUS CASTING OF MOLTEN MATERIAL INTO AN ELONGATED COOLING COMPOSITE MOLD CAVITY FOR OBTAINING A CONTINUOUS BAR FORMATION FROM SAID MATERIAL, THE MACHINE COMPRISING A PLURALITY OF MOVABLE COMPOSABLE CHILLS HAVING AT LEAST TWO REMOVABLY MATING CHILL PARTS DEFINING A LONGITUDINAL SECTION OF SAID ELONGATED MOLD CAVITY WHEN IN MATING POSITION, AND GUIDE MEANS FOR SAID MATING CHILL PARTS.

p 0, 1911 I M. GIADQRQU 3,605,868

MACHINE FOR THE CONTINUOUS CASTING OF MOLTEN MATERIALS IN IRON MOLDS OR CHILLS Filed Feb. 16, 1970 2 Sheets-Sheet 1 MASSlMO GIADOROU w AGENT INVENTOR.

Sept. 20, 1971 M. GIADOROU 3,605,358

MACHINE FOR THE CONTINUOUS CASTING 0F MOLTEN MATERIALS IN IRON MOLDS QR CHILLS 2 Sheets-Sheet 2 Filed Feb. 16, 1970 INVENTOR. MASSIMO GIADOROU Win34 United States Patent O1. Ii ce 3,605,868 MACHINE FOR THE CONTINUOUS CASTING F MOLTEN MATERIALS IN IRON MOLDS OR CHILLS Massimo Giadorou, Via priv. C. Battisti 1, Milan, Italy Filed Feb. 16, 1970, Ser. No. 11,551 Claims priority, application Italy, Feb. 24, 1969, 13,247/ 69 Int. Cl. B22d 1. /06

US. Cl. 164279 9 Claims ABSTRACT OF THE DISCLOSURE A machine for the continuous casting of molten material into an elongated cooling composite mold cavity for obtaining a continuous bar formation from said material, the machine comprising a plurality of movable composable chills having at least two removably mating chill parts defining a longitudinal section of said elongated mold cavity when in mating position, and guide means for said mating chill parts.

BACKGROUND OF THE INVENTION The present invention relates to a machine for the continous casting of molten material into a continuous string or bar or band with the aid of a series of mobile iron molds or chills performing a cyclic alternation.

Different types of machines for such continuous casting of molten materials such as aluminum and other metals are known. One of the known types, still in use at present, achieves the soldification of the molten metal by means of an elongated mold or chill of sufficient length formed by the peripheral groove of a wheel and a ribbon which closes the groove peripherally. Other types achieve the solidification between parallel ribbons suitably guided and laterally closed, or between two opposite cylinders.

Another type of machine, known in literature but scarcely applied, carries out the casting in a continuous series of composite twopart chills of the conventional type having two opposite clamshell-like parts, which are connected to each other by an articulated joint or hinge so as to form two revolving horizontal chain-tracks, one arranged over the other.

These types of machines, especially used for the casting of aluminum, foresee always the availability of a total length of chills equal to from 2 to 4 times the length of chills required and practically used at the moment of the solidification of the molten metal: this, just because the continuity of the casting is carried within chill zones which are parts of an assembly continuous in any case.

SUMMARY OF THE INVENTION Thus, an object of this invention is that of providing a machine for continuous casting in two-part chills with opposite clamshell-like parts wherein use is made of a series of chills whose total length is only slightly greater than the length of the casting cavity (defined by the intercommunicating opposite clamshell-like parts) strictly necessary for the solidification of the molten material.

Another object of this invention is that of realizing a machine which is particularly simple and efficient which, although using a traditional type of chill or mold, will allow very high production rates and a controlled and uniform solidification of the product, making it thus suited for the continuous operation under the most favourable technical and economical conditions.

These and still other objects, which will appear more clearly from the detailed description that follows, are achieved by a machine for the continuous casting of Patented Sept. 20, 1971 molten material into an elongated cooling composite mold cavity for obtaining a continuous bar formation from said material, the machine comprising a plurality of movable composable chills having at least two removably mating chill parts defining a longitudinal section of said elongated mold cavity when in mating position, guide means for said mating chill parts, said guide means having at least two facing forward motion stretches, at least two return motion stretches and respective winding sections connecting said forward motion stretches and said return motion stretches at each end thereof, respectively, first driving means for moving said chill parts along said forward motion stretches thereby to impart a forward motion to the chill parts on said forward motion stretches and to group such chill parts in line on said forward motion stretches, said first driving means, said guide means and said chill part having a structure allowing pairs of opposite chill parts to mate with each other and to form a row of abutting composite chills defining said elongated mold cavity, second driving means for imparting a return motion to the chill parts on said return motion stretches, said second driving means imparting a speed to said return motion, which is substantially greater than the speed of said forward motion, thereby to allow that the number of returning chill pairs is at least one, channel means for feeding the molten material into said mold cavity and cooling means for said chills.

BRIEF DESCRIPTION OF THE DRAWING The invention, with regard to its preferred but not exclusive form of embodiment, will be described hereinafter more in detail with reference to the attached drawings given for just illustrative and not limiting purposes, in which:

FIG. 1 represents a schematical side-view of a casting machine carried out according to the invention, without the chill cooling system;

FIG. 2 is a schematical view, in an increased scale, of a part of the machine of FIG. 1, and more particularly shows the devices foreseen on the feeding side of the chills;

FIGS. 3-4 show the cooling system of the chills falling within the scope of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The machine shown in the above cited figures is particularly suited (although not limited to it) for the production of a continuous bar or flat bar of aluminum with a constant rectangular cross-section, ready to be at once subjected to the usual known subsequent processings.

With particular reference to FIGS. 1 and 2, the machine of this invention consists of a supporting frame 1, hinged with one of its ends through pivots 2 on uprights 3 of the base and with the other end hinged on hydraulic pistons 4 or other like devices suitable for allowing varying inclinations or slants, with respect to the horizontal plane of the whole machine, to be imparted to the frame.

The operational zone of the machine, along which the casting and the solidification of the molten metal takes place, comprises two pairs of opposite and parallel guides 5 and 6' within which the advancing motion of the chills takes place; these guides 5 and 6' extend through turns into guides 5 and 6 thereby forming a pair of endless guides which are destined for the transfer of the chills from side B to side A of the machine by means of chains 17 and 18 which work as endless conveyor belts.

Between the pair of guides 5 and 6' there can be seen the series of chills required for the casting and marked 7-8-9-10-11, which are kept coupled to each other in order to form a continuous efiicient casting cavity. The pairs of valves or clamshell-like parts 7'-7", 88", 9'- 9", 10'10" and 11'11", which will be called hereinafter half-molds or chill parts, forming the individual chills, are mounted on trolleys moving between said endless guides and have their cavities mating with each other so as to form an elongated casting cavity reproducing the shape of the solidified bar P. Also the chills formed by the pairs of half-molds 12-12 and 13'-13" are mounted on trolleys.

Guides and 6' are in a slanting position, with respect to the horizontal plane, with an angle which, depending on the type and on the characteristics of the molten material to be solidified, may preferably vary between and 25. In the case of molten aluminum it has been found that the most suited angle of inclination amounts to about 20 with respect to the horizontal plane. However, if required, in practice the machine according to this invention may work also with slanting angles quite outside the above-mentioned range of inclinations.

On the lower part of half-molds 7", 8", 9", 10", 11", 12" and 13" there are fixed racks 14, 14' etc., which, when abutting chills slide along between guides 5' and 6, take up a character of continuity just like the casting cavity formed by the abutting half-molds.

A driving pinion 15, mounted in constant mesh with said racks, is provided for transmitting the forward movement of the chills from the feeding side A towards the outlet side B of the solidified bar P, while another driving pinion 16, likewise in constant mesh with said racks 14, is foreseen for creating a push in the same direction of the forward-movement from a side A to a side B of the machine, so as to ensure the constant abutment between chills 7-8-9-10. For this purpose, the pushing pinion 16 has a speed tendentially greater than that of the driving pinion 15, and it is mounted in combination with a friction-clutch system (not shown on the drawing) so that the push action on the racks be of an elastical or yieldable character and such as not to interfere with the feed-speed imparted by the driving pinion 15.

As clearly shown in FIGS. l and 2, the half-molds 13' and 13", forming the chill 13, are represented in the arriving position on the feed-side and are shown ready for the mating; on side B chill 11 has its own half-molds 11' and 11" in a partially open position (due to the loop of the guides 5 and 6) in order to free the solidified bar P. The half-molds thus prepare to return to side A of the machine by displacing along the outer sides of guides 5 and 6.

In this way the continuous and regular alternation of the series of chills is obtained.

The transfer or return motion of the half-molds from side B to side A of the machine is carried out by linked chains 17 and 18, endless like guides 5 and 6, said chains being driven by gearwheels 19-19 and 20-20.

Fixed to the two chains 17 and 18 are catches 21 and 22, respectively, suited for engaging, by pushing against suitable rollers on the trolleys, the half-molds releasing the solidified bar P, and for dragging said half-molds along the outer sides of guides 5 and 6 up to side A of the machine. Said catches release the valves just at the moment when there is a change in speed of the chills, i.e. when these chills arrange themselves so as to engage their racks with pinion 16 in order to be trailed at operational speed.

In order to transfer towards side A, the half-molds which open gradually on side B, the machine is set in such a way that, for instance, at each complete revolution of pinion there corresponds the passage of the rack of one chill (wherefore pinion 15 turns out to have the same number of teeth as the rack of each chill) and also one complete revolution of gearwheels 19-19 and 20-20.

Furthermore, still as an example, chains 17 and 18 have each a number of links that is thrice the number of teeth of one of the gearwheels and foresee three catches each (equal to those indicated by 21 and 22) arranged at equal distances so as to ensure the alternation (or advancement) by means of only one subsidiary chill, that is, by the chill formed by half-molds 12 and 12".

In fact, it will be understood that the speed imparted by the chains 17 and 18 to the half-mold on the return motion stretch 5 and 6 of the guides is far greater than the forward motion speed of the row of chills. In this way at least during the time in which a chill of the row travels along a distance corresponding to the length of one chill, the subsidiary chill on the return motion stretch may complete the entire return motion so that at least one subsidiary chill may be sufiicient for the cyclical interchange of the chills.

The lower catch 22 is mounted with a certain lead (advance) on the corresponding upper catch 21 in order to facilitate the mating of the half-molds at the moment of their arrival on side A.

Each half-mold carries on the contact plane one or two pins 23 suited for ensuring a perfect mating of each pair of half-molds and laterally they carry hooking plates 24-25 (FIG. 2, where the dotted lines show the position taken up after the mating).

In order to facilitate the opening of the half-molds on side B of the machine, there may be used the same means (plates 24-25) used for the mating of the oncoming half-molds, for instance, by placing them on the opposite ends of the half-molds (see FIG. 2) or by similar means with the same function.

By this arrangement it obtains that at each revolution of the driving pinion 15, the corresponding catches 21 and 22 of the conveying chain will push half-molds 11' and 11" up to the corresponding positions 12' and 12" and these two half-molds 1.2 and 12" up to the positions of half-molds 13' and 13". Likewise, all the chills enclosed between guides 5 and 6' will be moved on towards side B, that is, chill 8 will take up the position of chill 9 and so forth; chill 10 will have replaced chill 11.

Since in the circular stretches of guides 5 and 6, and more precisely, in the upper one on side A and in the lower part on side B, the own weight of the half-molds causes them to lose contact with their corresponding catches 21 and 22, gearwheels 19 and 20 carry radial stops 25 (those of wheel 19 are not visible in the figure) which accompany the half-molds along said circular stretches and release them again to the push of catches 21 and 22.

In the case that for any reason the half-molds should tend to stop before the meshing of the rack with pinion 16, they would be pushed forward by the pushing arms 27 (FIG. 2), mounted on wheels 19-20, until they reach the dragging mechanism.

Before starting the machine, that is, before starting with the casting, it will be necessary to close the cavity of one chill in order to avoid that the molten metal not yet solidified, fiows out at the other end of the chill, while streaming along the lower part of the chill before filling it; with the machine in operation, the chills will advance with a continuous and uniform motion within the guides 5 and 6' and in the same way will take place the alternating of the chills along the external stretches of the guides.

The molten aluminum will be fed into the casting cavity of the first chill through the feeding channel 28 and will gradually solidify inside the casting cavity by means of the cooling of the chills wherefore the solidified bar P will continuously come out on side B.

In order to carry out said cooling (FIGS. 1-3) a suitable fluid, for instance water, is made to flow through inside cavities 29-30, etc. of each half-mold. The water is fed in through filler-pipes 31-32, etc., and is continuously discharged through outlet pipes 33-34, etc.

In order to facilitate the inflow of the cooling water into said pipes during the forward motion of the chills, pipes 31-32 have their ends (FIG. 4) shaped into funnels 31'32, wherefore the water fed from the feeding conduits 35-36 can fiow in continuously without any spilling or losses.

The cooling of the chills may also be achieved with other fluid means, by changing, if necessary, the type of filler-pipes. This cooling system offers a high degree of regulability which, together with the variability of the casting speed, allows to influence the structural characteristics and the out-flow temperature of the product, so as to adapt them to the requirements of the subsequent processings.

With the machine according to the invention herein above described, it has been found that, in the case of the solidification of the molten aluminum, the total length of the chills used is little greater (infact, of the length of two chills) than the length of the casting cavity strictly necessary for the solidification of the molten metal. In general, said total length turns out to be comprised between about /2 and about A that necessary for other similar machines.

The possible casting speeds proved in the case of aluminum were comprised between 0.55 and 3.00 m./min.

Modifications and variants of the invention are possible without thereby falling outside the protective scope of this invention.

In fact it is evident that, the dimensions of the chills, their number, shape, as well as their pre-heating and cooling system, the number of subsidiary chills necessary for the alternation, the slant of the guides between which takes place the casting (which at the limit may vary from to 90) etc., will be established depending on the material used, on the dimensions and characteristics required for the product obtained, on its use at the time they come out of the machine, etc.

Also the advancing system for the chills between guides 5' and 6' may be varied: with racks placed either above or on the side of the chills, inverting the function of the two pinions, that is, by attributing to pinion 16 the driving function and to pinion 15 the braking function by giving it a lower speed than that of pinion 16; by substituting the rack and pinion motion by the motion through pushers, etc. There may also be arranged a temporary hooking up of the chills, which will take place only for the stretch between the guides, thereby eliminating the pushing pinion; this temporary coupling of the chills may also be obtained by offsetting the position of the upper half-mold with respect to the lower half-molds of the chills, wherefore their pins 23 will maintain the approaching.

What is claimed is:

1. A machine for the continuous casting of molten material into an elongated cooling composite mold cavity for obtaining a continuous bar formation from said material, the machine comprising a plurality of movable composable chills having at least two removably mating chill parts defining a longitudinal section of said elongated mold cavity when in mating position, guide means for said mating chill parts, said guide means having at least two facing forward motion stretches, at least two return motion stretches and respective winding sections connecting said forward motion stretches and said return motion stretches at each end thereof, respectively, first driving means for moving said chill parts along said forward motion stretches thereby to impart a forward motion to the chill parts on said forward motion stretches and to group such chill parts in line on said forward motion stretches, said first driving means, said guide means and said chill parts having a structure allowing pairs of opposite chill parts to mate with each other and to form a row of abutting composite chills defining said elongated mold cavity, second driving means for imparting a return motion to the chill parts on said return motion stretches, said second driving means imparting a speed to said return motion, which is substantially greater than the speed of said forward motion, thereby to allow that the number of returning chill pairs is at least one, channel means for feeding the molten material into said mold cavity and cooling means for said chills.

2. A machine according to claim 1, wherein said first driving means comprise rack sections fixed on said chills and at least one driving pinion constantly in mesh with said rack sections, said rack sections forming a continuous rack when said chills are part of said row of chills.

3. A machine according to claim 1, wherein said second driving means comprise endless chains forming a closed circuit, moving around gearwheels revolving at a speed greater than said forward motion speed and having pushing means removably engaging said chill parts when they are arranged on said return motion stretches and said winding sections thereof in order to release the bar formation of solidified metal and ensure the continuous alternation of the pairs of chill parts.

4. A machine according to claim 2, wherein said first driving means comprise at least another driving pinion in mesh with said rack sections and subjected to a speed tendentially greater than the speed of said driving pinion so as to form a forward push in the same direction of the forward motion of the chills without interfering with the driving action of the driving pinion, and a slipping friction transmission connected with said other driving pinion.

5. A machine according to claim 3, wherein said pushing means include catches keyed on said chains and stops fitted onto said gear-wheels, said catches and stops being spaced from each other in such a way as to ensure the alternation of one single chill at a time.

6. A machine according to claim 1, wherein each chill part has an abutting surface, at least one pin on said abutting surface suited for ensuring the perfect mating of the chill parts into pairs, a lateral lead-in plate for the coupling of the chill parts, the lead-in plates of mating chill parts being offset to each other in order to ensure said coupling, and avoid interference of the coupled leadin plates.

7. A machine according to claim 1, further comprising a supporting frame for the machine having hinge means at one end and lifting devices at the other end thereof in order to permit the inclination of the machine with respect to the horizontal plane.

8. A machine according to claim 7, wherein the inclination of the machine is in the range between 10 and 25 for casting aluminum.

9. A machine according to claim 1, wherein said cooling means comprise cavities in said chill parts, filling pipes for said cavities connected to said chill parts and having funnelshaped inlet mouths, so arranged as to partially overlap each other thereby avoiding the spilling of the water from said filler pipes during the forward motion of the chills, and discharge pipes for said cavities.

References Cited UNITED STATES PATENTS 2,597,046 5/1952 Sendmir 164-279X 2,804,667 9/1957 Townhill 164-279X 3,543,342 12/1970 Moran et a1. 164279X I. SPENCER OVERHOLSER, Primary Examiner I. E. ROETHEL, Assistant Examiner U.S. Cl. X.R. 164-87 

